Apparatus for relieving the symptoms of deep vein thrombosis

ABSTRACT

Apparatus for relieving the symptoms of deep vein thrombosis comprises a fabric envelope having on one surface a plurality of projections and on an opposed surface, one or more strips of a hook and loop-type fastener sold under the trademark Velcro® or similar material for releasably attaching the envelope to a carpeted floor surface. A container fits within the fabric envelope and comprises two side-by-side compartments which communicate with one another through one or more openings. A mouthpiece is provided in the container to enable the compartment to be inflated. The container includes a pocket above one of the two compartments of the container to receive a heating element.

This invention relates to apparatus for relieving the symptoms of deepvein thrombosis.

It is widely appreciated that being seated in relatively confined spacesfor long periods of time can lead to deep vein thrombosis, namelycoagulation of blood in a blood vessel or organ. Airline passengers onlong haul journeys have suffered from this condition, popularly referredto as “Economy Class Syndrome”. The condition is believed to arisethrough lack of exercise of the feet and legs and pressure appliedconsistently to the soles of a person's feet or the back of a person'sknees by the edge of the seat in which the person is positioned.

Devices seeking to prevent or reduce deep vein thrombosis have beenproposed previously. These proposals include a compression system forincreasing blood flow as disclosed in GB-A-2327888, an inflatablecompression garment as disclosed in GB-A-2271060, and an ambulatorypneumatic compression device as disclosed in GB-A-2263405. In the firstand second of these documents, blood circulation in a limb is stimulatedby a periodically inflatable sheet which is wrapped around a patient'sfoot. This is cumbersome to apply and requires an external pressuresource. It is, therefore, inappropriate for aircraft travel.GB-A-2263405 concerns an orthopaedic shoe connected to recipient cellswrapped around the calf and ankle of a user and operable to exert apumping effect to the cells as the user walks. Again, such a device isinappropriate for air travel.

The present invention sets out to provide apparatus capable ofpreventing, or at least reducing the likelihood of, deep vein thrombosisin airline passengers and others, which is easy to use, does not requirean external pressure source for operation and does not present a dangerto the safety of passengers when used in, for example, the confines ofan aircraft cabin.

According to the present invention in one aspect, there is providedapparatus for relieving the symptoms of deep vein thrombosis whichcomprises a container including first and second compartments each atleast partially filled with a flowable material and each produced atleast partially from a resilient material, an envelope housing thecompartments, and a pocket for receiving a heating element whichoverlies only one compartment of the container, an external surface ofthe envelope being formed with ribs, serrations or like projections.

The interiors of the compartments may be placed in communication withone another through one or more communicating passageways.

The envelope may be produced from a fabric, e.g. a woven fabric and theribs may be formed from a plastics material, from synthetic rubber, or arubber substance.

The compartments may be separated by a seam extending between sides ofthe container. Preferably the compartments are aligned one alongside theother. If the compartments are separated along a seam, the seam may bepartially discontinuous to define the communicating passageways.

Each container may be produced from a rubber or resilient plasticsmaterial and may be permanently sealed or fitted with a removable plug,stopper or the like. A mouthpiece may be provided to enable the interiorof the container to be filled with air by the user blowing air by mouthinto the container via the mouthpiece.

Alternative flowable materials include water or a solid granularmaterial may be employed. One compartment may, for example, containwater and the other air. Preferably, each compartment contains air.

A heating element may be permanently or releasably located within thepocket. Operation of the heating element produces a difference intemperature to exist between the contents of the two compartments.Preferably, the heating element comprises a portable heat pack whichcomprises a sealed flexible plastics bag containing a chemicallyreactive substance (typically sodium acetate) and a metallic disc whichwhen subjected to finger pressure or flexing produces a chemicalreaction within the reactive substance to generate heat. Typically, theheat generated persists for periods in excess of thirty minutes. Afterthis, the bag and the contents can be reactivated simply by placing thebag in boiling water. The bag can then be reused.

Means may be provided to attach the underside of the envelope to a floorsurface. This may comprise one or more suitably positioned pieces of ahook and loop-type fastener sold under the trademark Velcro®.

The container may be wholly produced from a resilient material;alternatively, the upper surfaces of each container may be produced fromresilient material. The shape and dimensions of the container and thatof the envelope are preferably such as to enable a seated user to placehis or her feet on the upper surfaces of the containers, downwardmovement of the user's toes causing the respective heel to lift andvice-versa. This action is assisted if the interiors of the containersare in communication with one another.

The ridges or other projections formed on an outer surface of theenvelope enable a user to rub his/her feet over the ridges to encourageblood circulation, and the heating element (if used) produces atemperature differential between the feet of the user which againencourages circulation.

In a preferred embodiment of the invention, the apparatus comprises acontainer of a rubber-like material located within an open-endedmaterial envelope. The container includes two compartments placed incommunication with one another through a partially discontinuous seam.In this embodiment both of the compartments are filled with air. Onecompartment includes a mouthpiece to enable air to be blown by mouthinto that compartment and into the other compartment via thecommunicating passageways or vents produced by the partiallydiscontinuous seam. The envelope carries on its lower surface strips ofa hook and loop-type fastener sold under the trademark Velcro® to enableit to be secured to a carpeted floor surface immediately in front of,for example, an airline seat and positioned to enable the user of theseat readily to place his or her feet on the enveloped compartments ofthe container. The container has an exterior pocket positioned over oneof the compartments for receiving a heating element which operates toraise the temperature of the contents of that compartment. The heatingelement comprises a portable heat pack which comprises a sealed flexibleplastic bag containing a chemically reactive substance (typically sodiumacetate) and a metallic disc which when subjected to finger pressure orflexing produces a chemical reaction within the reactive substance togenerate heat.

In use of the preferred embodiment, the user of the apparatus places hisor her feet on the envelope above the compartments of the container thanthen flexes his or her feet thereby inducing a rocking movement whichencourages the flow of blood through the person's body. The temperaturedifference caused by the presence of the heating element also encouragesflow of blood through the person's body. The ribbing applied to theupper surface of the envelope enables the user to move his or her feetover the surface of the ribbing again to stimulate blood circulation.

In another aspect, the invention provides apparatus for relieving thesymptoms of deep vein thrombosis which comprises a fabric envelopehaving on one surface a plurality of projections and on an opposedsurface means for releasably attaching the envelope to a floor surface,a container dimensioned to fit within the fabric envelope and comprisingtwo side-by-side compartments which communicate with one another throughone or more openings and a mouthpiece to enable the compartment to beinflated, and a pocket provided above one of the two compartments of thecontainer dimensioned to receive a heating element.

The invention will now be described by way of example only withreference to the accompanying diagrammatic drawings in which:

FIGS. 1 and 2 are respectively plan and side views of an envelope whichforms part of apparatus in accordance with the invention;

FIG. 3 is a section taken through a container forming part of apparatusin accordance with the invention;

FIG. 4 is a partial section taken along line IV—IV of FIG. 3;

FIG. 5 is a section taken along lines V—V of FIG. 3; and

FIG. 6 is a plan view of alternative apparatus in accordance with theinvention.

The apparatus for relieving symptoms of deep vein thrombosis illustratedin FIGS. 1 and 2 of the drawings comprises a fabric envelope 1 whoseupper surface is formed with ribs 2. The ribs extend upwardly from padssecured to the upper surface of the envelope. The ribs may extend acrossthe full width of the envelope. More or less ribs than shown may beprovided. Typically, the height of each rib is or the order of 1.5 mm. Atypical height range is between 1 mm and 3 mm. The ribs are typicallyproduced from a plastics, synthetic rubber or a rubber substitute. Thespacings between neighbouring ribs is sufficient to stimulate blood flowin stockinged or bare feet of a user when the feet are moved backwardsand forwards over the ribs. Other patterns of ribs or projections may beused. For example, the pattern may take the form of a matrix.

The surface of the envelope remote from the ribs 2 carries strips of ahook and loop-type fastener sold under the trademark Velcro® (not shown)to enable the envelope to be attached to a carpeted floor surface.

The container 3 shown in FIGS. 3 to 5 is typically produced fromplastics, a natural rubber or a rubber-like substitute material andcomprises side ribs 4 and a closure 5 which either selectively orpermanently seals the container interior. Typically, the thickness ofthe material is 1.25 mm. A typical range of thicknesses is from 1 mm to2.5 mm. The container is divided into two side-by-side compartments 3A,3B by an internal seam 7 (shown in broken line) which extends over thefull width of the container. An external pocket extends over one of thecompartment 3A. The compartment is dimensioned to receive a portableheat pack as described above. Each of the compartments 3A, 3B ispartially filled with a flowable material, e.g. air, water or granularmaterial.

The alternative apparatus shown in FIG. 6 comprises a generallyrectangular air filled container 6 divided along lateral seams 12 todefine two compartments 3A, 3B. The seams extend over only a part of thelateral extent of the container, neighbouring seams defining discretepassageways for the flow of air from one compartment to the other. Theseams may be created by a heat welding process. Pocket 8 is positionedabove compartment 3A. This is defined between the upper surface of thecontainer and a sheet of plastics or other material secured to the uppersurface of the container. The dimensions of the pocket are sufficient toreceive a portable heat pack.

A mouthpiece 10 is provided to enable the container to be partiallyinflated simply by the user blowing air by mouth in the compartments. Inuse, the container is positioned in the fabric envelope as describedpreviously. One advantage of this embodiment is that depression of onecompartment causes air to flow through the openings defined between theseams 12 to the other compartment thereby automatically lifting therespective foot of the user.

It will be appreciated that modifications can readily be made to theapparatus described without departing from the true scope of theinvention as set out in the appended claims.

1. Apparatus for relieving the symptoms of deep vein thrombosis whichcomprises a container including first and second compartments each atleast partially filled with a flowable material and each produced atleast partially from a resilient material, an envelope having anunderside and housing the compartments, and a pocket for receiving aheating element which overlies only one compartment of the container, anexternal surface of the envelope being formed with projections. 2.Apparatus as claimed in claim 1 wherein the compartments are separatedby a seam which is partially discontinuous to define communicatingpassageways between the compartment interiors.
 3. Apparatus as claimedin claim 1 wherein the container is produced from a rubber or resilientplastics material and is permanently sealed or fitted with a removableplug.
 4. Apparatus as claimed in claim 1 wherein the flowable materialis a fluid, a gas or a solid granular material.
 5. Apparatus as claimedin claim 1 wherein the envelope is produced from a woven fabric. 6.Apparatus as claimed in claim 1 wherein the projections are producedfrom plastics, or natural or synthetic rubber.
 7. Apparatus as claimedin claim 1 further comprising a heating element, wherein the heatingelement comprises a portable heat pack which comprises a sealed flexibleplastic bag containing a chemically reactive substance and a metallicdisc which when subjected to finger pressure or flexing produces achemical reaction within the reactive substance to generate heat. 8.Apparatus as claimed in claim 1 wherein means are provided to attach theunderside of the envelope to a floor surface.
 9. Apparatus for relievingthe symptoms of deep vein thrombosis which comprises a fabric envelopehaving on one surface a plurality of projections and on an opposedsurface means for releasably attaching the envelope to a floor surface,a container dimensioned to fit within the fabric envelope and comprisingtwo side-by-side compartments which communicate with one another throughone or more openings and a mouthpiece to enable the compartment to beinflated, and a pocket provided above one of the two compartments of thecontainer dimensioned to receive a heating element.